This application claims priority of Japanese Application No. 2000-364328, filed Nov. 30, 2000, the complete disclosure of which is hereby incorporated by reference.
a) Field of the Invention
The present invention relates to a building, a door, a doorknob, a handrail, and a signal transmission method, capable of transmitting a millimeter-wave signal from a transmission station to a reception station within a building.
b) Description of the Related Art
Since personal computers and multi-function type telephones have become popular, there are strong demands for a plurality of electronic appliances having communication functions are desired to be set within homes. Further, a so-called xe2x80x9chome-use automation systemxe2x80x9d has been proposed. For instance, a user may issue an instruction to operate an air conditioner installed in his/her home via a telephone line while this user is outside his/her home. Also, a user may control an image recording apparatus from the outside of his/her home so as to record a desirable television program by this image recording apparatus.
In such a home-use automation system, it may be so supposed that users issue instructions via a telephone line or the like to the respective home electric appliances. In this case, telephone lines and the like need to be connected to the home electric appliances.
Under such circumstances, the following technical solution may be conceived; while a user does not directly send the instructions to the respective home electric appliances, wireless communication may be carried out among the respective home electric appliances in such a manner that an instruction issued by the user is received by a predetermined terminal apparatus, and then, this instruction is transferred from this terminal apparatus to one or more other home electric appliances.
In this case, when these home electric appliances are connected to each other through signal cables, the signal cables are installed within a house, which may deteriorate interior appearances. Therefore, the communication system may be preferably used by utilizing the existing home-use electric power lines, or by utilizing wireless communication systems.
In a communication system using the existing home-use electric power lines, for instance, a mother telephone set and daughter telephone sets are communicable with each other via the existing home-use electric power lines.
On the other hand, as to wireless data communication available among home electric appliances, various standards such as Bluetooth have been proposed. In the Bluetooth standard, wireless communication in frequency of 2.45 GHz is used, and data communication is realized in the transfer speed of approximately 1 Mbps (bit per second) by wireless among home electric appliances such as personal computers and personal digital assistances (PDAs).
Another sort of wireless data communication is known in this technical field, e.g., a wireless LAN (Local Area Network) system such as the one defined in IEEE 802.11 which provides data communication speed of 11 Mbps in the frequency range of 2.4 GHz.
In the case where the above-explained wireless communication systems are utilized, generally speaking, a wireless data reaching distance is shortened under an indoor environment due to a few or more obstacles such as walls in some arrangements, compared with that under an outdoor environment.
In the case where the wireless data communication is carried out in the above-explained frequency range, the electromagnetic waves can pass through only small number of obstacles, so that data communication may be established. However, in a future case where wireless communication in the frequency range of millimeter wavelengths may be realized so as to further increase the transfer speed of the wireless communication, signals at such millimeter wavelengths can hardly pass through obstacles, due to the straight propagation characteristic and the reflection characteristic of these millimeter-wave signals. As a consequence, the following difficulties may occur; the wireless communication can hardly be established over doors and walls at the ordinary intensity level of electromagnetic waves of millimeter wavelengths.
Further, when such wireless communication will be realized between floors by wireless signals at millimeter wavelengths, a ceiling and the like may act as an obstacle. As a result, it is practically difficult that the wireless communication between floors may be carried out by the wireless signals at millimeter wavelengths.
Accordingly, the present invention has an object to provide a building, a door, a doorknob, a handrail, and a transmission method, capable of executing wireless communication with millimeter-wave signals under an indoor environment.
To achieve the above-explained object, a building according to an aspect of the present invention, is characterized by comprising: a first antenna mounted on the side of one surface of a door or a wall, for sensing a signal at a millimeter wavelength; a second antenna mounted on the side of the other surface of the door or the wall, for radiating a signal at a millimeter wavelength; a first receiver for receiving the millimeter-wave signal sensed via the first antenna, and for converting the sensed millimeter-wave signal into an electric signal; and a first transmitter for converting the electric signal which is received and converted by the first receiver into the millimeter-wave signal and for transmitting the converted millimeter-wave signal via the second antenna.
As a result, even when obstacles such as a door and a wall are present on a signal transmission path, wireless communication can be carried out by using signals at millimeter wavelengths within a building.
Furthermore, a building according to another aspect of the present invention, in the above-mentioned aspect of the present invention, is characterized by further comprising: a first transfer unit including a third antenna for sensing a signal at a millimeter wavelength, and a second receiver for receiving the millimeter-wave signal sensed by the third antenna to convert the received millimeter-wave signal into an electric signal and for transmitting the converted electric signal via a home-use electric power line, the first transfer unit being installed around a wall outlet of a home-use power supply on a predetermined floor of a home; and a second transfer unit including a fourth antenna for radiating a signal at a millimeter wavelength, and a second transmitter for receiving the electric signal which is transmitted via the home-use electric power line to convert the received electric signal into the millimeter-wave signal and for transmitting the converted millimeter-wave signal via the fourth antenna, the second transfer unit being installed around a wall outlet of the home-use power supply on a floor different from the predetermined floor.
As a result, even in a case where the transmission path extends over floors, wireless communication can be carried out by employing the signals having millimeter wavelengths within the building, while the existing home-use electric power line is utilized. Accordingly, high-speed and low-cost information communication can be realized with large capacity by wireless.
Further, in a building according to another aspect of the present invention, besides the above-mentioned aspect of the present invention, both the first receiver and the first transmitter operate only when the door is closed.
As a result, electric power consumed by both the first receiver and the first transmitter can be suppressed. It should be noted that when the door is opened, since millimeter-wave signals may directly pass through a doorway, even if operations of both the first receiver and the first transmitter are stopped, there is no problem in the transmission of millimeter-wave signals.
Moreover, a building according to a further aspect of the present invention, is characterized by comprising: a first antenna provided on one end portion of a handrail which is mounted along stairs or a corridor, for sensing a signal at a millimeter wavelength; a second antenna provided on the other end portion of the handrail, for radiating a signal at a millimeter wavelength; a receiver for receiving the millimeter-wave signal which is sensed by the first antenna and for converting the received millimeter-wave signal into an electric signal; and a transmitter for converting the electric signal which is converted by the receiver into a millimeter-wave signal, and for transmitting the converted millimeter-wave signal via the second antenna.
As a consequence, even in such cases where obstacle such as the stairs is present on the transmission path and that millimeter-wave signals can be hardly transmitted through a narrow corridor, wireless communication can be carried out by using millimeter-wave signals inside the building. Further, since handrails are often required for going up and down the stairs, the users do not have a sense of incongruity when such handrails equipped with the transmitter/receiver are installed. In addition, since one or more handrails are often utilized unless information communication is needed, there is almost no increase in the cost of equipment when information communication are carried out using the present handrail.
Further, a door according to an aspect of the present invention is characterized by comprising: a first antenna mounted on any one of one knob portion of a doorknob, a fixing portion for fixing the doorknob on one surface of the door, and one surface of the door, for sensing a signal at a millimeter wavelength; a second antenna mounted on any one of the other knob portion of the doorknob, another fixing portion for fixing the doorknob on the other surface of the door, and the other surface of the door, for radiating a signal at a millimeter wavelength; a receiver for receiving the millimeter-wave signal which is sensed by the first antenna and for converting the received millimeter-wave signal into an electric signal; and a transmitter for converting the electric signal which is converted by the receiver into the millimeter-wave signal and for transmitting the converted millimeter-wave signal via the second antenna.
As a consequence, even in a case where the door as an obstacle is present on the transmission path, wireless communication can be carried out by using millimeter-wave signals inside the building. Further, since a door can be individually replaced with the door already fixed as a fixture, the door according to the present invention can be applied even to such a building which has already been constructed. Thus, wireless communication with millimeter-wave signals may be realized in general houses by replacing the existing door with the door of the present invention.
Furthermore, a door according to another aspect of the present invention, in the above-mentioned aspect of the present invention, is characterized in that both the receiver and the transmitter operate only when the door is closed.
As a result, electric power consumed by both the receiver and the transmitter can be suppressed. It should be noted that when the door is opened, since millimeter-wave signals may directly pass through a doorway, even if operations of both the receiver and the transmitter are stopped, there is no problem in the transmission of millimeter-wave signals.
A doorknob according to an aspect of the present invention is characterized by comprising: a first antenna mounted on one knob portion, for sensing a signal at a millimeter wavelength; a second antenna mounted on the other knob portion, for radiating a signal at a millimeter wavelength; a receiver for receiving the millimeter-wave signal which is sensed by the first antenna and for converting the received millimeter-wave signal into an electric signal; and a transmitter for converting the electric signal which is converted by the receiver into the millimeter-wave signal and for transmitting the converted millimeter-wave signal via the second antenna.
As a consequence, even in a case where the door as an obstacle is present on the transmission path, wireless communication can be carried out by using millimeter-wave signals inside the building. Further, since a doorknob can be individually replaced by another doorknob as a fixture, the doorknob according to the present invention can be applied even to such a building which has already been constructed. Thus, wireless communication with millimeter-wave signals may be realized in general houses by replacing the existing doorknob with the doorknob of the present invention at little expense.
Moreover, a doorknob according to another aspect of the present invention is characterized in that both the receiver and the transmitter operate only when the door having the doorknob is closed.
As a result, electric power consumed by both the receiver and the transmitter can be suppressed. It should be noted that when the door is opened, since millimeter-wave signals may directly pass through a doorway, even if operations of both the receiver and the transmitter are stopped, there is no problem in the transmission of millimeter-wave signals.
In addition, a handrail according to an aspect of the present invention is characterized by comprising: a first antenna mounted on one end portion of the handrail, for sensing a signal at a millimeter wavelength; a second antenna mounted on the other end portion of the handrail, for radiating a signal at a millimeter wavelength; a receiver for receiving the millimeter-wave signal which is sensed by the first antenna and for converting the received millimeter-wave signal into an electric signal; and a transmitter for converting the electric signal which is converted by the receiver into the millimeter-wave signal and for transmitting the converted millimeter-wave signal via the second antenna.
As a result, even in cases where transmissions of the millimeter-wave signals directly to another floor are hardly achieved due to a ceiling as a shield, and that millimeter-wave signals can be hardly propagated through a narrow corridor, this handrail of the present invention is installed, so that wireless communication can be carried out by using millimeter-wave signals through such stairs and/or corridor within the building. Further, since handrail is often utilized unless information communication is needed, there is almost no increase in the cost of equipment when information communication is performed with the above-mentioned handrail.
Further, a transmission method according to an aspect of the present invention, is characterized by comprising the steps of: sensing a signal at a millimeter wavelength by a first antenna on the side of one surface of a door or a wall, which is present on a transmission path defined from a transmission station to a reception station; receiving the sensed millimeter-wave signal; converting the received millimeter-wave signal into an electric signal; and transmitting the electric signal via a second antenna as the millimeter-wave signal on the side of the other surface of the door or the wall.
As a result, even when obstacles such as the door and the wall are located in the transmission path, wireless communication can be carried out by employing millimeter-wave signals inside the building.
Furthermore, a transmission method according to another aspect of the present invention is characterized by comprising the steps of: sensing a signal at a millimeter wavelength by a first antenna on the side of one end portion of a handrail mounted along stairs or a corridor which is present on a transmission path defined from a transmission station to a reception station; receiving the sensed millimeter-wave signal; converting the received millimeter-wave signal into an electric signal; and transmitting the electric signal via a second antenna as the millimeter-wave signal on the side of the other end portion of the handrail.
As a result, even in cases where transmissions of millimeter-wave signals directly to another floor are hardly achieved due to a ceiling as a shield, and that millimeter-wave signals can be hardly propagated through a narrow corridor, this handrail of the present invention is installed, so that wireless communication can be carried out by using millimeter-wave signals through stairs and/or the corridor within the building. Further, since handrail is utilized unless information communication is needed, there is almost no increase in the cost of equipment when information communication is performed with the above-mentioned handrail.